In an automotive vehicle, a selector lever is disposed in the vehicle's passenger compartment, and is manually shifted stepwise in the longitudinal direction of the vehicle so as to select one of the power transmission ranges including a parking range (P), a reverse range (R), a neutral range (N), a drive range (D) and low speed ranges (I,II).
A conventional selector lever is not positively locked when in the parking position, and thus it can be inadvertently shifted by hand. If this happens when the vehicle is parked on a slope, the vehicle will start to move down the slope with gathering momentum.
With a view to avoid such a danger, various devices for locking the selector lever have been proposed. For example, a selector lever locking device of interlock type is disclosed in JP-A-60-135352.
In that disclosed locking device, an ignition key cannot be removed from a key cylinder until the selector lever has been set in the parking position. When the key is removed from the key cylinder while the selector lever is in the parking position, the selector lever is then locked in the parking position and cannot be shifted to any other position.
Describing in greater detail, when a release button provided on the selector lever is depressed to set the selector lever in the parking position, a detent pin provided on one end of an internal rod of the selector lever enters into a recess of a detent plate. The detent pin engages a cutout formed at one end of a bell crank to cause swinging movement of the bell crank. Due to this swinging movement of the bell crank, a cable or a rod connected to the other end of the bell crank is moved to cause a corresponding sliding movement of a slider connected to the other end of the cable or rod, thereby permitting rotational movement of the key cylinder. When the key cylinder is rotated to a locking position, and the key is then removed from the key cylinder, the slider is blocked against return movement by its engagement with the key cylinder. That is, the bell crank is held in the state in with its cutout is engaged by the detent pin thus preventing release of the selector lever when set in the parking position.
Therefore, even when the button provided on the selector lever is depressed under the above condition, the detent pin cannot be moved downward because its downward movement is restricted by the cutout of the bell crank, and the selector lever is locked in the parking position.
The bell crank is used to prevent the downward movement of the detent pin when the selector lever is set in the parking position. However, the relation between the stroke of the cable and that of the detent pin is determined by the lever ratio of the bell crank, and this is generally rectilinear as shown by a broken line in FIG. 5. Therefore, when the selector lever is set in the parking position, the detent pin must be kept engaged by the parking-purpose recess of the detent plate. However, the detent pin can become disengaged from the recess of the detent plate in the event that the connection cable or rod is subjected to permanent elongation or deformation.
Further, because the connection cable or rod extends through an outlet opening, the design of the outlet opening has been somewhat restricted.